92 lines
2.1 KiB
Go
92 lines
2.1 KiB
Go
|
|
package utils
|
|||
|
|
|
|||
|
|
import (
|
|||
|
|
"fmt"
|
|||
|
|
"math"
|
|||
|
|
"testing"
|
|||
|
|
)
|
|||
|
|
|
|||
|
|
func Test_fastSqrt(t *testing.T) {
|
|||
|
|
// 测试用例
|
|||
|
|
testCases := []float64{2, 4, 10, 16, 25, 100, 1000, 0.5, 0.01, 1e-20}
|
|||
|
|
|
|||
|
|
fmt.Println("测试卡马克快速平方根算法与标准库的对比:")
|
|||
|
|
fmt.Println("数值\t快速算法结果\t标准库结果\t绝对误差")
|
|||
|
|
fmt.Println("--------------------------------------------------------------")
|
|||
|
|
|
|||
|
|
for _, x := range testCases {
|
|||
|
|
fastResult := fastSqrt(x)
|
|||
|
|
stdResult := math.Sqrt(x)
|
|||
|
|
error := math.Abs(fastResult - stdResult)
|
|||
|
|
|
|||
|
|
fmt.Printf("%.10g\t%.10g\t\t%.10g\t\t%.2e\n",
|
|||
|
|
x, fastResult, stdResult, error)
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
// 测试整数版本
|
|||
|
|
fmt.Println("\n测试整数快速平方根算法:")
|
|||
|
|
fmt.Println("数值\t快速算法结果\t标准库转换结果")
|
|||
|
|
fmt.Println("--------------------------------------")
|
|||
|
|
|
|||
|
|
for _, x := range []int{2, 4, 10, 16, 25, 100, 1000} {
|
|||
|
|
fastResult := fastSqrtInt(x)
|
|||
|
|
stdResult := int(math.Sqrt(float64(x)))
|
|||
|
|
|
|||
|
|
fmt.Printf("%d\t%d\t\t%d\n", x, fastResult, stdResult)
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
func BenchmarkMathSqrt(b *testing.B) {
|
|||
|
|
testValues := []float64{2, 4, 10, 16, 25, 100, 1000, 0.5, 0.01, 1e-20}
|
|||
|
|
b.ResetTimer()
|
|||
|
|
|
|||
|
|
for i := 0; i < b.N; i++ {
|
|||
|
|
for _, x := range testValues {
|
|||
|
|
_ = math.Sqrt(x)
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
func BenchmarkFastSqrt(b *testing.B) {
|
|||
|
|
testValues := []float64{2, 4, 10, 16, 25, 100, 1000, 0.5, 0.01, 1e-20}
|
|||
|
|
b.ResetTimer()
|
|||
|
|
|
|||
|
|
for i := 0; i < b.N; i++ {
|
|||
|
|
for _, x := range testValues {
|
|||
|
|
_ = fastSqrt(x)
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
func BenchmarkFastSqrtCarmack(b *testing.B) {
|
|||
|
|
testValues := []float64{2, 4, 10, 16, 25, 100, 1000, 0.5, 0.01, 1e-20}
|
|||
|
|
b.ResetTimer()
|
|||
|
|
|
|||
|
|
for i := 0; i < b.N; i++ {
|
|||
|
|
for _, x := range testValues {
|
|||
|
|
_ = fastSqrtCarmack(x)
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
func BenchmarkMathSqrtInt(b *testing.B) {
|
|||
|
|
testValues := []int{2, 4, 10, 16, 25, 100, 1000, 10000, 100000}
|
|||
|
|
b.ResetTimer()
|
|||
|
|
|
|||
|
|
for i := 0; i < b.N; i++ {
|
|||
|
|
for _, x := range testValues {
|
|||
|
|
_ = int(math.Sqrt(float64(x)))
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
func BenchmarkFastSqrtInt(b *testing.B) {
|
|||
|
|
testValues := []int{2, 4, 10, 16, 25, 100, 1000, 10000, 100000}
|
|||
|
|
b.ResetTimer()
|
|||
|
|
|
|||
|
|
for i := 0; i < b.N; i++ {
|
|||
|
|
for _, x := range testValues {
|
|||
|
|
_ = fastSqrtInt(x)
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
}
|